JPH0731973B2 - Electromagnetic trip device - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an electromagnetic tripping electromagnet such as a circuit breaker,
In particular, the present invention relates to a suitable electromagnet structure for preventing vibration noise of the contact surface between the non-magnetic cylinder and the movable iron core.

BACKGROUND OF THE INVENTION FIG. 1 shows an electromagnetic trip device provided inside a conventional circuit breaker. Reference numeral 1 is a non-magnetic cylinder that is inserted into a yoke 3 and fixed by solder 2, and inside thereof a control spring 4 for controlling the operation and a movable iron core 5 having a small diameter portion and a large diameter portion.
Is built in and is sealed by a fixed iron core 6. At this time, the inside of the cylinder is an air layer. Reference numeral 8 is a current coil wound around the non-magnetic cylinder 1.

With the above configuration, the following operation is performed.

When an overcurrent flows through the current coil 8, magnetism is generated in the yoke 3 and the moving iron core 5, the moving iron core 5 overcomes the load of the control spring 4, moves toward the upper fixed iron core 6, and instantly. Arrive at the fixed iron core 6. As a result, the movable iron core 7, which is joined to the yoke 3 at one end, is attracted with further increase in magnetic force. The attraction of the movable iron core 7 causes the other end to blow out the trip device 9 of the circuit breaker to open the contacts.

In the above operation, when an alternating current near the rated current value (100%) is applied to the current coil 8, the inner wall surface of the non-magnetic cylinder 1 and the outer circumference of the large diameter portion of the moving iron core 5 come into contact with each other, Further, since the magnetic force for moving the moving iron core 5 in the direction of the upper fixed iron core 6 is balanced with the load of the control spring 4, the movable iron core 5 includes the bottom surface of the non-magnetic cylinder 1 and the bottom surface of the large diameter portion of the movable iron core 5. There is a problem in that the two sides come into contact with each other and generate an oscillating sound due to the alternating magnetic field.

[Object of the Invention]

It is an object of the present invention to provide an electromagnetic trip device having a structure that does not generate vibration noise inside a non-magnetic cylinder up to near an operating current value.

[Outline of Invention]

The present invention provides a non-magnetic cylinder having an opening at one end and the other end closed, a fixed iron core fixed at one end of the non-magnetic cylinder so as to close the opening, and an outer circumference of the non-magnetic cylinder. An electromagnetic coil that is wound around and energized with an alternating current, and a non-magnetic cylinder that is formed in the shape of the letter "L" and is inserted into the short side of the letter "L". A yoke arranged so that the tip is located near the fixed core, and a "K" shape that is formed so that one side of the "K" shape is attracted to the fixed core when the electromagnetic coil is excited. A movable iron core slidably locked to the tip of the long side of the “L” shape of the yoke near the bent part of the character, and slidably housed inside the non-magnetic cylinder to accommodate the electromagnetic coil. When moving, it moves toward the fixed iron core and forms a magnetic path between it and the yoke through the movable iron core, and this movement inside the non-magnetic cylinder In an electromagnetic tripping device having a control elastic body arranged between a core and a fixed iron core, a compression spring arranged between a bottom surface of the other closed end of the nonmagnetic cylinder and a moving iron core, and A vibration absorbing material fixed to the outer circumference of the iron core is provided, the inside of the non-magnetic cylinder is sealed by a fixed iron core so as to form an air layer, and the control elastic body and the compression spring are arranged separately from the inner surface of the non-magnetic cylinder. It is characterized by.

Example of Invention

An embodiment of the present invention will be described with reference to FIGS. 2 and 3. FIG. 2 is an overcurrent trip device for a circuit breaker. Reference numeral 1 denotes a non-magnetic cylinder that is inserted into a yoke 3 and fixed by solder 2. Inside it, a small diameter portion is provided on the control spring 4 and fixed iron core 6 side, and a large diameter is provided on the lower side of the small diameter portion. A movable core 12 having a portion formed therein and having a synthetic resin 11 shown in FIG. As the synthetic resin, a heat-shrinkable Teflon tube or a nylon shrink tube is used. Further, a compression spring 13 is built in between the bottom surface of the non-magnetic cylinder 1 and the bottom surface of the large-diameter portion of the movable iron core 12, and is sealed by the fixed iron core 6. A movable iron core 7 that is joined to one end of the yoke 3 is provided above the fixed iron core 6. Reference numeral 8 is a current coil wound around the non-magnetic cylinder 1.

Next, the operation of the above configuration will be described.

If an overcurrent flows through the current coil 8, the yoke 3 and the moving core
A magnetic force is generated in 12, and the moving iron core 12 overcomes the load of the control spring 4, moves toward the upper fixed iron core 6, and reaches the fixed iron core 6 in an instant. As a result, the movable iron core 7, which is joined to the yoke 3 at one end, is attracted with the increase in magnetic force.
The attraction of the movable iron core 7 causes the other end to blow out the trip device 9 of the circuit breaker to open the contacts.

In the configuration and operation as described above, when a current near the rated current value is applied to the current coil 8, the magnetic force that attracts the moving iron core 12 toward the upper fixed iron core 6 is balanced with the load of the control spring 4. Because of the alternating magnetic field, the moving iron core
Although 12 vibrates, a spring 13 is provided between the bottom surface of the non-magnetic cylinder 1 and the bottom surface of the large diameter portion of the moving iron core 12, and further the inner wall surface of the non-magnetic cylinder 1 and the outer circumference of the large diameter portion of the moving iron core 12 are provided. Since the synthetic resin 11 is fixed between them, the collision between the moving iron core 12 and the inner wall surface and bottom surface of the non-magnetic cylinder due to vibration is buffered, and almost no vibration noise is generated. The resin also reduces the resistance to sliding. Further, since the control spring 4 and the compression spring 13 are separated from the inner surface of the non-magnetic cylinder 1, even if these springs vibrate due to the vibration of the moving iron core, contact with the inner surface of the non-magnetic cylinder 1 is prevented. Vibration noise can be prevented. Further, since the inside of the non-magnetic cylinder 1 is an air layer, it is not necessary to prevent oil leakage and the structure is simplified.

The results of measuring the noise in the above example are as follows. That is, in an anechoic room with background noise of 27 dB, when the measurement distance is 1 m, the example of Fig. 1 is 50 dB, the example of Fig. 2 is 27 dB, and 50 c.
When m is 54 dB in the example of FIG. 1, 28 dB in the example of FIG. 2, 59 dB in the example of FIG. 1 and 30 dB in the example of FIG.

The following may be considered as another embodiment. That is,
A synthetic resin layer is formed on the inner circumference of the non-magnetic cylinder 1. In this case, a synthetic resin cylinder is inserted into a non-magnetic cylinder, or a resin is coated on the inner circumference of the cylinder 1, and a movable iron core 12 is inserted inside the resin layer and slidably loaded.

As still another example, the non-magnetic cylinder can be made of synthetic resin, and this cylinder can also be used as the coil bobbin 8. At this time, the cylinder does not have to have a closed structure, and may be any one that can slidably support the moving iron core.

〔The invention's effect〕

According to the present invention, it is possible to obtain an electromagnetic trip device having a simple structure and capable of easily preventing the generation of vibration noise.

[Brief description of drawings]

FIG. 1 is a sectional view of an electromagnetic trip device portion having a conventional structure, FIG. 2 is a sectional view of an electromagnetic trip device portion showing an embodiment of the present invention, and FIG. 3 is a perspective view of a movable iron core assembly. It is a figure. 1 ... Non-magnetic material, 2 ... Solder, 3 ... Yoke, 6 ... Fixed iron core, 7 ... Movable iron core, 8 ... Current coil, 9 ... Tripping device, 10 ... Control spring, 11 ...... Synthetic resin, 12 …… Movable iron core, 13 …… Spring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliographic reference Sho 53-24469 (JP, U) Actual 54-24653 (JP, U)

Claims (1)

[Claims] 1. A nonmagnetic cylinder having an opening at one end and the other end closed, a fixed iron core fixed to the one end of the nonmagnetic cylinder so as to close the opening, and the nonmagnetic. An electromagnetic coil that is wound around the outer circumference of the body tube and is supplied with an alternating current, and a non-magnetic body tube that is formed in the shape of the letter “L” and is fitted to the short side of the letter “L”. Yoke arranged so that the tip of the long side of the letter is located near the fixed iron core, and one side of the letter "K" is formed into the fixed iron core when the electromagnetic coil is excited. "Ku" to be sucked into
A movable iron core slidably locked to the tip of the long side of the letter "L" of the yoke near the bent portion of the character "", and slidably housed inside the non-magnetic cylinder. A moving iron core that moves toward the fixed iron core when the electromagnetic coil is excited to form a magnetic path between the yoke and the yoke via the movable iron core, and the moving iron core and the fixed iron core inside the non-magnetic cylinder. An electromagnetic tripping device having a control elastic body disposed between the moving iron core and the bottom surface of the closed non-magnetic body cylinder at the other end and the moving iron core; Of the non-magnetic body cylinder is sealed by the fixed iron core so as to form a gas layer, and the control elastic body and the compression spring are separated from the inner surface of the non-magnetic body cylinder. Electromagnetic trip device characterized by being arranged as follows.